TY - GEN

T1 - Steady-state solutions of a propagating borehole

T2 - 2011 20th IEEE International Conference on Control Applications, CCA 2011

AU - Perneder, Luc

AU - Detournay, Emmanuel M

PY - 2011/11/7

Y1 - 2011/11/7

N2 - Deep boreholes with complex geometries are now drilled with the help of rotary steerable systems (RSS), which are downhole robots capable of steering the bit by either applying a force on the borehole walls (push-the-bit systems) or by tilting the bit (point-the-bit systems). This paper explores the existence of stationary borehole geometries in the form of vertical helical trajectories. These non-trivial solutions, which represent the equilibrium points of the dynamical equations governing the evolution of the borehole, correspond to situations where the deformed configuration of the bottomhole assembly (BHA) remains invariant during the propagation of the borehole, i.e., the BHA moves inside the created borehole as a rigid body. Formulation of the model yields a system of linear equations in terms of the radius and pitch of the helical boreholes. A parametric analysis of the solution for the idealized case of rigid BHA with one stabilizer shows the region of existence of helical trajectories and the dependence of the pitch and radius of the helix on the control parameters.

AB - Deep boreholes with complex geometries are now drilled with the help of rotary steerable systems (RSS), which are downhole robots capable of steering the bit by either applying a force on the borehole walls (push-the-bit systems) or by tilting the bit (point-the-bit systems). This paper explores the existence of stationary borehole geometries in the form of vertical helical trajectories. These non-trivial solutions, which represent the equilibrium points of the dynamical equations governing the evolution of the borehole, correspond to situations where the deformed configuration of the bottomhole assembly (BHA) remains invariant during the propagation of the borehole, i.e., the BHA moves inside the created borehole as a rigid body. Formulation of the model yields a system of linear equations in terms of the radius and pitch of the helical boreholes. A parametric analysis of the solution for the idealized case of rigid BHA with one stabilizer shows the region of existence of helical trajectories and the dependence of the pitch and radius of the helix on the control parameters.

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U2 - 10.1109/CCA.2011.6044464

DO - 10.1109/CCA.2011.6044464

M3 - Conference contribution

AN - SCOPUS:80155192403

SN - 9781457710629

T3 - Proceedings of the IEEE International Conference on Control Applications

SP - 905

EP - 911

BT - 2011 IEEE International Conference on Control Applications, CCA 2011

Y2 - 28 September 2011 through 30 September 2011

ER -